feature: azure document intelligence as a segmentation model

[akhileshsharma99]

Add the ability to use azure document layout analysis for the segmentation model. This will be configurable through the following field in the upload form:

pipeline: "Azure"

The output will be unified so SegmentType will now look like this:

type SegmentType =
  | "Title"
  | "SectionHeader"
  | "Text"
  | "List item"
  | "Table"
  | "Picture"
  | "Caption"
  | "Formula"
  | "Footnote"
  | "PageHeader"
  | "PageFooter"
  | "Page"

The following will be mapped from Azure layout analysis result to the output above:

• paragraphs.role.null -> Text
• paragraphs.role.title -> Title
• paragraphs.role.sectionHeading -> SectionHeader
• paragraphs.role.pageNumber -> PageFooter
• results.figures[idx] -> Picture
• results.tables[idx] -> Table
• results.figures[idx].caption.elements -> Caption
• results.tables[idx].caption.elements -> Caption

NOTE
No formula support as formulas can be inside paragraphs and that breaks our current implementation.
Any paragraphs inside the Picture and Table region will be removed to match our unified output.